1. Field of the Invention
The present invention relates to a magnetic tape cartridge, in which a single tape reel with magnetic tape wound thereon is rotatably housed within a cartridge case, and in which a tape leader pin for pulling the magnetic tape out of the cartridge case is firmly attached to the leading end of the magnetic tape.
2. Description of the Related Art
In magnetic tape cartridges, which are being used as storage media that are employed in external storage units for computers, etc., there is known a type where a single tape reel with magnetic tape wound thereon is rotatably housed within a cartridge case. This magnetic tape is employed to archive data for computers, etc. Since important information has been stored, the magnetic cartridge is constructed so that problems, such as tape jamming, etc., do not occur and that the magnetic tape is not pulled out of the cartridge case inadvertently.
The magnetic tape has an elongate tape leader pin firmly attached to the leading end thereof. When this magnetic tape cartridge is loaded into a recording-reproducing unit, a leader-pin catching member on the side of the recording-reproducing unit engages the tape leader pin and pulls out the magnetic tape from the cartridge case. On the other hand, when the magnetic tape cartridge is unloaded from the recording-reproducing unit, the magnetic tape is rewound on the tape reel and the tape leader pin is returned into the cartridge case by the leader-pin catching member. The cartridge case is formed by fastening upper and lower cases of synthetic resin together with a plurality of small screws. Near a tape leader opening formed in the cartridge case, the tape leader pin is detachably held at the upper and lower ends thereof by a spring member.
The spring member for detachably holding the tape leader pin, incidentally, repeats sliding action each time the magnetic tape cartridge is loaded into or unloaded from the recording-reproducing unit. Because of this, the sliding surfaces of the tape leader pin and the spring member are worn away and the sliding resistance therebetween increases. As a result, the pulling-in-and-out of the tape leader pin through the tape leader opening cannot be smoothly performed. In the worst case, the pulling-in-and-out of the tape leader pin cannot be performed at all.
In addition, in the case that the spring member is formed from a plate spring, it is punched out from a plate, and consequently, burrs are liable to occur at the edge. If there are burrs on the sliding surface of the elastic arm portion of the spring member (plate spring) that contacts the tape leader pin, when the sliding surface of the elastic arm portion abuts the tape leader pin to hold the tape leader pin, the burrs cause scoring of the tape leader pin surface every time sliding action is performed between the elastic arm portion and the tape leader pin (i.e., when the magnetic tape cartridge is loaded into or unloaded from the recording-reproducing unit). Because of this, the sliding resistance between the elastic arm portion and the tape leader pin is increased. Consequently, the pulling-in-and-out of the tape leader pin through the tape leader opening cannot be smoothly performed. In the worst case, there is a fear that the pulling-in-and-out of the tape leader pin cannot be performed at all.